Hoisting apparatus for power operated shovels



W. RUDDOCK June 14, 1932.

HOISTING APPARATUS FOR POWER OPERATED SHOVELS Filed June 29, 1931 2 Sheets-"Sheet 1 llIIIIIIIIIIIIIIIIIIIIIIII ENE W. RUDDOCK June 14, 1932.

HOISTING APPARATUS FOR POWER OPERATED SHOVELS Filed June 29, 1931 2 Sheets-Sheet 2 Patented June 14, 1932 PTENT OFFICE WILLIAM RUDDOGK, OF WHITTIER, CALIFORNIA I-IOISTING APPARATUS FOR POWER OPERATED SHOVELS Application filed June 29,

This invention relates generally to the type of power operated shovels commonly known as gas shovels, more specifically to means for regulating or controlling the movement of the dipper during digging operations, and is thence downwardly around the pulley of the dipper, upward therefrom and wound around the drum with the dead end thereof being connected to the drum. The drum and sheave being arranged to rotate in unison by frictional clutch engagement or independent- 1y by application of a brake to the drum, the clutch and brake being operated through links and leversin such a manner that when the clutch is engaged the brake is released and vice versa.

In order that the above construction may operate in the most efiicient manner, it is necessary to provide a drum ofsufliciently large diameter to prevent wear .on the cable due to winding and unwinding thereon during operation, this in turn requires a sheave wheel of corresponding diameter to obtain the proper ratio between the sheave and. drum. Although this apparatus operates in the manner set forth, it has been found that upward movement of the dipper is limited due to contact with its pulley with said sheave wheel. 7

The object of the present invention is to provide an apparatus of the character referred to arranged in such a manner that a cable drum of sufficiently large diameter to prevent wear of the cable may be employed without increasing the diameter of the sheave wheel over which the cable to the dipper pulley passes.

Other objects and advantages will be apparent from the following description, reference being bad to the accompanying draw- 1931. Serial No. 547,661.

Fig. l is a side elevation of a power-shovel showing the improved hoisting apparatus in operative position thereon.

Fig. 2 is a front elevation of the'shovel taken in the direction of the arrow 2 of Fig. 1. 55

Fig. 3 is a top plan view of the hoisting apparatus in applied position to the boom.

Fig. t is a side elevation taken in the direction indicated by the arrow 3 of Fig. 2.

Fig. 5 is a section taken through the boomv 60 and apparatus as indicated by line 5-5 of Fig. 4. i

Fig. 6 is a section taken through the hoisting apparatus on line 55 of Fig. 2.

Fig. 7 is a fragmentary section taken through the drum showing the connection for the dead end of the cable.

Fig. 8 is a detail section taken on line 88 of Fig. 7.

Figs. 9 and 10 are fragmentary side elevations of the boom and apparatus illustrating the operation of the apparatus.

Referring more specifically to the drawings, 10 generally designates a power shovel of the gas-air type provided with a hoisting drum 12, boom 1 and dipper 15 connected to the usual stick 16. The apparatus of the .invention generally designated at 18 is adapted to be mounted on the outer end of the boom, and is constructed as follows:

Mounted in boxes 20 secured to the side members 22 and 23 of the boom is a spindle 24 upon which is rotatably mounted a sheave plurality of pins 32 slidably mounted in openings 33 formed in the hub 34 of the sheave wheel and serve to form engagement between the sheave and sprocket, the sprocket being provided with a flange 35 having openings 37 formed therein to receive the ends of the pins. Clutch member 30 is actuated by a shifter which consists of a split ring 38 engaging a groove formed in the periphery of the clutch member, and a pair of arms 39 secured to a rock shaft 40 mounted in a suitable bearing 4:1 secured to the boom member 23, the arms having openings formed in their free ends engaging pins 42 projecting from the ring 38.

Secured to the shaft -10 is an arm 44 which is connected by a clevis 45 to a rod a6 secured to or formed integral with a piston 47 disposed in a cylinder 48 mounted on the boom.

Shifting of the clutch member to effect engagement of the sprocket and sleeve is accomplished by admitting compressed air into the cylinder, the clutch member being normally disengaged by the action of an expansion coil spring d9 encircling the rod 46 with its opposite ends engaging a stop plate 50 and the piston.

Compressed air is admitted to the cylinder through a pipe line 52 controlled by a three way valve 53 adapted to admit or exhaust air from said cylinder, the pipe leading to a source oft-supply of compressed air, not shown.

Rotatably mounted on a spindle 54 disposed in openings formed in the side members of the boom adjacent the outer ends thereof is a drum 56, and an idler sheave 58. The hoisting cable designated at C- passes from the hoisting drum 12 over sheave wheels 26 and idler sheave 5S, thence downwardly around the dipper pulley 59 upwardly therefrom, and is connected to the drum by a. pivotally mounted cinch generally designated at 60 (see Figs. 7 and 8) which serves to permit winding of the cable on the drum in either direction without twisting it.

The cinch consists of a member 61 having a tapered opening 62 therein adapted to receive a loop 63 formed at the end of the cable which is held in place thereon by a wedge 64, the member having oppositely disposed removable pins 65 projecting into alined openings in the flange 66 of the drum, and a lug 67 formed on the drum.

Cable C is wrapped around the sheave in at least one coil to prevent slippage, rotation of the sheave being transmitted to the drum by an endless chain 68 engaging the sprocket- 28 and a sprocket 70 secured to the sheave wheel.

The drum 56 is of smaller diameter than the sheave 26, while the sprocket 52- is larger than the sprocket 28, the relative size of the sprockets, however, may be varied according to the speed of the dipper required, i. e., during raising or lowering; it being particularly noted that the diameter of the sheave 26 should be equal to or larger than that of the hoistin drum, which in turn should be larger than the drum 56.

The apparatus provides means whereby the dipper may be raised or lowered at selective speeds without changing the speed of the hoisting drum, or at a greater or reduced speed than is possible with the dead end of the cable secured to a fixed point.

lVhen the shove-l is employed for hard digging, it is desirable to move the dipper at slow speed, in this instance, the cable -C is wrapped around the drum 56 in the opposite direction to that on the sheave 26, and

the dipper raised with the sheave 26 and sprocket 28 engaged.

During upward movement the dipper will be raised at reduced speed, and at the same time additional lifting power will be applied thereto due to the cable unwinding from the drum 56. The cable will rewind on the drum during lowering of the dipper, the action of which checks its downward movement and tends to reduce wear on the brakes of the hoisting drum.

Under conditions when the shovel is employed for light digging or removing loose material, it is advantageous to move the dip per at high speed; this is accomplished by winding the cable on the drum 56 in the same direction to that of the sheave 26, as shown in Fig. 10. The movement of the dipper will then be accelerated due to winding of the cable on the drum 56 during upward movement, and from unwinding of it from the drum during downward movement.

By disengaging the sheave 26 and sprocket 28, the dipper may be raised or lowered at usual speed, the drum remaining stationary with the dead end of the cable connected thereto, as shown in Fig. 9.

It will be understood that when the shovel is employed for either hard or light digging, the sheave and sprocket remain engaged, and should be disengaged only when the dipper is resting on the ground with the cable slack.

I claim:

1. In a power shovel including a boom, a hoisting cable, and a dipper having a pulley, a spindle disposed in openmgs formed in the side members of said boom adjacent the outer ends thereof, a drum mounted on said spindle, an idler sheave mounted on said spindle, a second spindle mounted on the side members of the boom rearwardly of said first spindle, a sheave wheel of larger diameter than said drum mounted on said second spindle, and transmission between said sheave and drum, the hoisting cable adapted to be passed around said sheave over said idler pulley around the dipper pulley and connected to said drum.

2. In a power shovel including a boom, a hoisting cable, and a dipper having a pulley, a spindle disposed in openings formed in the side members of said boom adjacent the outer ends thereof, a drum mounted on said spindle, an idler sheave mounted on said spindle, a second spindle mounted on the side members of the boom rearwardly of said first spindle, a sheave wheel of larger diameter than said drum mounted on said second spindle, a sprocket mounted on said second spindle, a sprocket secured to said drum, a chain passing over the sprocket on said second spindle and the sprocket secured to said drum, and means for engaging said sheave with the sprocket on said second shaft, the hoisting cable adapted to be passed around said sheave over said idler pulley around the dipper pulley and connected to said drum.

3. An apparatus of the character described comprising a spindle, a cable drum rotatably mounted on said spindle, a chain sprocket secured to said cable drum, a pulley mounted on said spindle, a second spindle, a sheave Wheel of larger diameter than said drum mounted on said second spindle, a sprocket mounted on said second spindle, an endless chain engaging said sprockets, a clutch member slidably mounted on said second spindle,

and means for shifting said clutch member,

whereby said sheave Wheel and sprocket may be engaged or disengaged for the purposes set forth.

In testimony whereof I aflix my signature.

WM. RUDDOCK. 

